Computing pioneer Vannevar Bush outlined the web's core idea - hyperlinked pages - in 1945, but the first person to try to build on the concept was a freethinker named Ted Nelson, who in 1965 envisioned his own scheme, which he called "Xanadu". But he had little success connecting digital bits on a useful scale and his efforts were known only to an isolated group of disciples. Few of the hackers writing code for the emerging web in the 1990s knew about Nelson or his hyperlinked dream machine.

At the suggestion of a computer-savvy friend, I got in touch with Nelson in 1984, a decade before Netscape made Marc Andreessen a millionaire. We met in a dark dockside bar in Sausalito, California. Folded notes erupted from his pockets, and long strips of paper slipped from overstuffed notebooks. He told me about his scheme for organising all the knowledge of humanity. Salvation lay in cutting up 3 x 5 cards, of which he had plenty.

Legend has it that Ted Nelson invented Xanadu as a remedy for his poor memory and attention deficit disorder. He was certain that every document in the world should be a footnote to some other document, and computers could make the (hyper)links between them visible and permanent. He sketched out complicated notions of transferring authorship back to creators and tracking payments as readers hopped along networks of documents, what he called the docuverse. He spoke of "transclusion" and "intertwingularity" as he described the grand utopian benefits of his embedded structure.